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HISTORY OF BRITISH FERNS. 
Asplenium marinum, Linnceus. 
The Sea Spleenwort (Plate XIV. fig. 1.) 
This very handsome maritime evergreen Fern grows 
profusely on our south-western rocky coasts and in the 
Channel Isles, and extending to France and Spain, to 
Madeira and the Canaries. In cultivation it thrives most 
luxuriantly in the atmosphere of a damp hothouse, where 
it forms, in a comparatively short time, a ^dense mass of 
the deepest green, and often reaching a foot and a half in 
length. In a cold frame, if kept closed, well-established 
plants will continue in health, progressing slowly, and 
never acquiring half the size of those grown in heat. In 
the climate of London it does not prosper, nor, as far as 
we know, survive, if planted on exposed rockwork. 
It is a tufted-growing species, with linear or linear- 
lanceolate fronds, usually six or eight inches long, of the 
deepest glossy green, with a smooth, rather short, dark- 
brown stipes. The fronds are simply pinnate, with stalked 
pinnse, connected at their base by a narrow wing, which 
extends along the rachis ; their form is either obtusely 
ovate or oblong, unequal at the base, the anterior base 
being much developed, while the posterior is, as it were, 
